Brain

ITHACA, N.Y. - Scientists and graduate students with minority identities who conduct fieldwork report being stalked, followed, sexually assaulted, harassed, threatened, having guns pulled on them and police called on them.

These issues threaten minority-identity researchers' physical health and safety during fieldwork, while also affecting their mental health, productivity and professional development.

A paper on the topic, "Safe fieldwork strategies for at-risk individuals, their supervisors and institutions," was recently published in the journal Nature Ecology and Evolution. The article - written by Amelia-Juliette Demery and Monique Pipkin, graduate students in the field of ecology and evolutionary biology - describes how peers, mentors, departments and institutions can all help to address these problems.

"When we solicited input from students in our department, we found that a lot of these personal experiences and the associated proactive measures that they took following those experiences were pretty universal and extended beyond just the color of someone's skin," Demery said.

The paper was originally intended as an internal document for the Department of Ecology and Evolutionary Biology, but feedback from department graduate student, postdoctoral and faculty reviewers encouraged Demery and Pipkin to widen the scope to apply more universally inside and outside of academia. The authors queried and received feedback from their department sources, and from sources at diversity and inclusion committees at the Cornell College of Agriculture and Life Sciences and the American Ornithological Society.

"Amelia Demery and Monique Pipkin have done such an important service to outline and explain strategies to keep field researchers safe, particular those who are at risk because of their minority identity," said Jeremy Searle, chair and professor in the Department of Ecology and Evolutionary Biology. "We have to do everything possible to ensure individuals are not hindered from doing field research because of identity prejudice, and this paper is a really important contribution for ensuring that," he said.

In their responses, researchers described feeling threatened based on their race/ethnicity, gender, sexual orientation, gender identity, religion and/or disability. Such experiences can also occur when American scientists travel internationally.

"Field safety is an issue for everyone," Pipkin said. "There is a lack of general field safety training."

In addition, such experiences take a toll on a scientist's or student's ability to do their work.

"If you have two graduate students, one may not perform as highly as another simply because they can't collect as much data because they are trying to mediate issues of being a woman in the field alone, being a person of color in the field alone, and having to always look over their shoulder," Pipkin said.

"It's an immense emotional and mental strain," Demery said.

These problems can be compounded, she said, by supervisors and advisers of different backgrounds who lack experiences of being 'othered,' and may respond with disbelief and skepticism.

Addressing these problems, Pipkin said, is everyone's responsibility. Individuals should prepare themselves by notifying others where and when they are collecting data, and conduct research with others when possible. Peers may check in on lab mates when they know they are in the field and be prepared to get help in emergencies. And supervisors must educate themselves, understand the specific field risks their students face and prepare their researchers ahead of time.

On department and institutional levels, fieldwork safety presents systemic challenges requiring standardizing safety protocols, Demery said. Such measures can include: developing and mandating field safety, harassment and first aid training; training supervisors; evaluating institutional practices and removing barriers to entry in the sciences; understanding and addressing risks at specific field sites; and hiring diverse faculty.

Demery and Pipkin plan to continue leading discussions across campus, hold workshop seminars and webinars, and design a template for how others can lead conversations on fieldwork safety issues.

The black rats weren't supposed to be there, on Palmyra Atoll. Likely arriving at the remote Pacific islet network as stowaways with the U.S. Navy during World War II, the rodents, with no natural predators, simply took over. Omnivorous eating machines, they dined on seabird eggs, native crabs and whatever seed and seedling they could find.

When the atoll's managers -- the U.S. Fish and Wildlife Service, The Nature Conservancy and Island Conservation -- were planning to conduct a rat eradication project, UC Santa Barbara community ecologist Hillary Young and her research group saw it as an unusual opportunity. They had already been visiting Palmyra regularly to track another non-native species -- the coconut palm -- to see whether it was spreading invasively in the area, potentially impacting the nesting seabird population and changing the island's soil composition. They had plots where they were monitoring trees in various stages of growth and survival; how would the vegetation respond to the eradication of the island's main seed and seedling eater?

"Prior to the eradication, most of the understory of Palmyra was either bare ground -- sandy soil or coral rubble -- or covered in a carpet of ferns," said Ana Miller-ter Kuile, a graduate student researcher in the Young Group and lead author of a study that appears in the journal Biotropica. The rats were quick to eat seeds and young plants coming out of the ground, and they frequented the canopy as well, often nesting in the coconut palms and eating coconuts.

Eradication of the rats -- which was conducted in 2011 -- did in fact result in a resurgence of vegetation on Palmyra. And not only that. The Asian tiger mosquito was wiped out, while two species of land crab emerged, adding to the atoll's biodiversity.

But rarely is ecology easily untangled. In the years that followed eradication, Palmyra's understory did indeed fill with juvenile trees as seeds that hit the ground were allowed to take root. Only they were often not the Pisonia or other native trees that would have been the more ideal forests for the native seabirds and animals of Palmyra.

"I was on the island in 2012, just after the eradication and could easily navigate through the open jungle understory," Miller-ter Kuile said. "Two years later when I went back, I was wading through an infuriating carpet of seedlings that were taller than me, tripping over piles of coconuts." While the researchers found a 14-fold increase in seedling biomass, most of these new seedlings were juvenile coconut palms, their proliferation left unchecked by the removal of the rats.

"Rats were basically eating almost every nut before it even reached the forest floor," Miller-ter Kuile said. "I knew that rats could have an impact, I just didn't expect it to be this large." In the absence of rats, according to a population model the researchers built based on a decades' worth of data on coconut seed production, growth and survival, the coconut palms' population growth rate increased by 10% -- enough to eventually overtake the island, had the managers not stepped in with an aggressive coconut palm removal project.

The coconut palm invasion is a problem for places like Palmyra Atoll, as it shifts the island's ecology away from native plants and animals.

"Coconuts have a very different 'nutritional' profile from the native tree species on this island, with much more carbon and less nitrogen," Miller-ter Kuile said. "When these trees die, because they have different nutrient profiles from native plants, they are likely to break down differently -- and more slowly -- and influence rates of decomposition." In addition, she said, native seabirds do not nest in coconut palms, which would deprive the atoll of the nutrients in their guano, which, in turn, "would lead to what would likely be a fairly nutrient-poor system, which discourages other native plants from growing in those areas."

Continuing their restoration of the island, Palmyra's managers were working to remove the vast majority of the island's millions of coconut palms to give local species a chance to dominate, a project that is currently on hold due to the COVID-19 pandemic.

Anticipating the indirect downstream effects, such as potential shifts in ecology toward other invasive species, could become part of a more holistic island rodent eradication effort, Miller-ter Kuile said.

"Wildlife management, in particular, has a history of being single-species focused, which often means that a lot of time and energy is put into producing or controlling a species without considering the broader effects of that management effort on all of the rest of the species in that ecosystem," she said. According to the study, "documenting the variation in invasive rodent diet items, along with long-term surveys, can help prioritize island eradications where restoration is most likely to be successful."

"The 'accidental experiment' of our long-term monitoring of trees in this project I think provides a rare opportunity to quantify the immediate and longer-term effects of eradication," she said.

Groping around in your bag for your keys can be a daily ordeal. I'm not going to list the catalogue of junk in my bag, but I can distinguish every article by touch. Our fingertips are exquisitely engineered, deftly detecting the differences between surfaces and shapes, but we are not the only animals that touch objects. 'A whole host of fishes contact the bottom of bodies of water, plants or other animals using their fins', says Adam Hardy from The University of Chicago, USA, leading Hardy and his graduate advisor, Melina Hale, to wonder whether fish may also be able to feel surface differences with their fins. The duo publish their discovery that goby fins are as touch sensitive as primate finger tips in Journal of Experimental Biology at https://jeb.biologists.org.

However, before they could begin unravelling the question, Hardy and Hale had to find a fish that seems to spend a lot of time in touch with riverbeds and the bottom of lakes. 'Round gobies (Neogobius melanostomus) were a great choice for these experiments given that they are a bottom-dwelling fish that love to perch on rocks and other materials', says Hardy, who biked from the university campus to Lake Michigan during the summer to catch the fish. 'It's always a good day when you can go fishing for work', he chuckles. After collecting a few gobies, Hardy filmed the fish as they manoeuvred over a piece of slate or a wavy piece of plastic on the tank bottom, and also when they wedged themselves against the side of the tank. Sure enough, the fish's fins splayed out over each of the surfaces, contacting the structures like a hand laid upon them. Yet, to find out whether the fins were providing the fish with different touch sensations, Hardy knew he had to record nerve signals from individual fin rays.

Gently brushing a short horizontal bar moving along a fin ray toward the tip at speeds ranging from 5mm/s to 20mm/s, Hardy recorded the electrical signals in nerves as the bar moved over the fin and it was clear that the fins sensed when they were being touched. In addition, each nerve only sensed contact along a tiny portion of each fin ray, possibly allowing the fish to feel fine surface details. But, were the fins sensitive enough to detect the difference between different grades of gravel?

This time, Hardy designed a rotating wheel with 2 mm wide ridges along the edge - separated by gaps of 3, 5 or 7mm - to mimic sediments ranging from coarse sand to granules and pebbles. Then he rolled each wheel along the fish's fin rays at speeds ranging from 20 to 80mm/s. 'It took numerous design iterations to create the wheels', says Hardy, but as he painstakingly recorded the nerve signals produced when the ridges contacted the fin rays, the nerve signals synchronised with each ridge contacting the ray. 'They matched the pattern of the ridges moving across the skin even as the speed of the wheel increased', he adds. Most impressively, the gobies' fins seemed to be as sensitive to the coarse surfaces as monkey finger pads.

'Primates are often held up as the gold standard in tactile sensitivity, so it was really exciting to see that fish fins exhibit a similar tactile response', says Hardy. He and Hale also suspect that the goby's tactical sensitivity may have originated far back in evolution. 'This primate hand-like touch also suggests that the ability to detect surface differences via touch has been around a lot longer than we previously thought', he says.

Systems which can emit a stream of single photons, referred to as quantum light sources, are critical hardware components for emerging technologies such as quantum computing, the quantum internet, and quantum communications.

In many cases the ability to generate quantum light on-demand requires the manipulation and control of single atoms or molecules, pushing the limit of modern fabrication techniques, and making the development of these systems a cross-disciplinary challenge.

In new research, published in Nature Materials, an international multidisciplinary collaboration led by the University of Technology Sydney (UTS), has uncovered the chemical structure behind defects in white graphene (hexagonal boron nitride, hBN), a two dimensional nanomaterial that shows great promise as a platform for generating quantum light.

The defects, or crystal imperfections, can act as single photon sources and an understanding of their chemical structure is critical to being able to fabricate them in a controlled way.

"hBN single photon emitters display outstanding optical properties, among the best from any solid state material system, however, to make practical use of them we need to understand the nature of the defect and we have finally started to unravel this riddle," says UTS PhD candidate Noah Mendelson and first author of the study.

"Unfortunately, we cannot simply combine powerful techniques to visualize single atoms directly with quantum optics measurements, so obtaining this structural information is very challenging. Instead we attacked this problem from a different angle, by controlling the incorporation of dopants, like carbon, into hBN during growth and then directly comparing the optical properties for each, " he said.

To realise this comprehensive study, the team, led by Professor Igor Aharonovich, chief investigator of the UTS node of the ARC Centre of Excellence for Transformative Meta-Optical Materials (TMOS), turned to collaborators in Australia and around the world to provide the array of samples needed.

The researchers were able to observe, for the first time, a direct link between carbon incorporation into the hBN lattice and quantum emission.

"Determining the structure of material defects is an incredibly challenging problem and requires experts from many disciplines. This is not something we could have done within our group alone. Only by teaming up with collaborators from across the world whose expertise lies in different materials growth techniques could we study this issue comprehensively. Working together were we finally able to provide the clarity needed for the research community as a whole," said Professor Aharonovich.

"It was particularly exciting as this study was enabled by the new collaborative efforts with collaborators Dipankar Chugh, Hark Hoe Tan and Chennupati Jagadish from the TMOS node at the Australian National University, " he said.

The scientists also identified another intriguing feature in their study, that the defects carry spin, a fundamental quantum mechanical property, and a key element to encode and retrieve quantum information stored on single photons.

"Confirming these defects carry spin opens up exciting possibilities for future quantum sensing applications, specifically with atomically thin materials." Professor Aharonovich said.

The work brings to the forefront a novel research field, 2D quantum spintronics, and lays the groundwork for further studies into quantum light emission from hBN. The authors anticipate their work will stimulate increased interest in the field and facilitate a range of follow up experiments such as the generation of entangled photon pairs from hBN, detailed studies of the spin properties of the system, and theoretical confirmation of the defect structure.

"This is just the beginning, and we anticipate our findings will accelerate the deployment of hBN quantum emitters for a range of emerging technologies," concludes Mr. Mendelson.

(Carlisle, Pa.) - Does a well-dressed president make for a better president? Yes, says political scientist David O'Connell. According to new research published in the journal White House Studies, O'Connell, an associate professor of political science at Dickinson College who studies American politics with a focus on religion and pop culture, argues style plays an underappreciated role in presidential politics and has meaningful consequences for presidential power.

O'Connell examined first-person memoirs and historical news sources to demonstrate how presidents can accomplish three goals through their style: communicate messages, enhance their political position and identify with important political constituencies. For example:

President Clinton sent a message by choosing a tie with trumpets during the historic White House meeting between Israeli PM and Yitzhak Rabin and PLO leader Yasser Arafat as a Biblical reference to the falling walls of Jericho.

President Kennedy, who preferred shabby dress in his years as a Congressman, enhanced his political position by updating his image to alleviate concerns about his youth.

President George W. Bush identified with rural voters by favoring cowboy attire, sometimes even while he was in Washington.

O'Connell also makes an argument for formality. "Better-dressed presidents are more likely to be better presidents since they will avoid the kinds of negativity that have historically greeted presidents who dressed more informally," O'Connell writes.

He points out some presidential style faux pas:

President Obama, known for shrugging off fashion decisions, was criticized for wearing a tan suit, which was perceived as too casual, to an appearance discussing serious issues with Syria.

Presidents Ford and Carter dressed casually to distinguish themselves from President Nixon, whom they perceived to be an inaccessible, pomp-and-circumstance president. Carter was first president to appear before the country in a sweater, a much-lampooned fashion choice that still gets critics talking.

President Clinton was so image conscious, he once closed half of LAX's runways for a haircut onboard an idling Air Force One by Beverly Hills hairstylist Christophe.

President Nixon's failed photo-op trying to one-up a beachcombing, sun-kissed Kennedy by walking a California beach in dress pants, white shirt and shined, wingtip shoes.

While almost no political scientists have analyzed the implications of style, O'Connell argues it is no secret that groups in society often make political statements through what they choose to wear or not to wear. He concludes scholars would be wise to consider style more closely, as there is powerful evidence that appropriately fashionable presidents helped their causes, while style faux pas have done damage to others.

Downy mildew is the biggest threat to spinach production around the world. While the pathogen has a short life cycle (approximately a week), it can produce millions of spores during the spinach growing season. Overhead sprinkler irrigation systems and dew formation on cool nights leads to more moisture, which enables these spores to infect the spinach.

Scientists at the University of Arkansas explored the relationship between available moisture and disease establishment and in a recent article they demonstrated that removing moisture decreased both spore survival and disease. Even a 30-minute dry period reduced spore germination to almost zero. Spores were unable to recover and cause disease on spinach.

In another experiment, they found that the micro-environment of a leaf surface can facilitate spore survival. They covered spinach plants with a spore solution and allowed the plants to dry out for different periods of time. They found that when the spores were on the plants, they were better at surviving in dry conditions but after enough time they found a reduction in disease. They also showed that standing water on leaves is essential for the spores to cause disease. These findings can be leveraged to design better disease management strategies for growers.

"We were also interested in understanding how new races of the downy mildew pathogen originate," explained Braham Dhillon, the first author of the paper. "The pathogen produces another type of long-lived spore known as an oospore, that can become dormant and survive harsh weather and remain viable in soil for long periods of time. But very little is known about the role of oospores in the life cycle of the spinach downy mildew pathogen."

Dhillon and colleagues were able to artificially produce oospores in the lab by mating two different strains of the downy mildew pathogen. This is a critical step in trying to determine the environmental factors that control oospore dormancy and germination.

"We demonstrated that oospores are produced abundantly in commercial spinach production areas in Arizona and California, the largest spinach growing area in the U.S.," said Dhillon. "This was the first direct evidence that different strains of the spinach downy mildew were present, can mate, and produce hybrid progeny in the field and potentially contribute to emergence of new pathogenic races of the pathogen." For more information about this study, read "Sporangiospore Viability and Oospore Production in the Spinach Downy Mildew Pathogen, Peronospora effusa" published in Plant Disease.

BOSTON - An evolving understanding of cancer that incorporates the physical properties of tumors and their surrounding tissues into existing biologic and genetic models can direct cancer researchers down previously uncharted avenues, potentially leading to new drugs and new treatment strategies, say investigators from Massachusetts General Hospital (MGH), Harvard Medical School (HMS) and the Ludwig Center at HMS.

"We believe that progress in cancer research relies on close collaboration between cancer biologists, oncologists, physical scientists and engineers. A comprehensive understanding of the physical hallmarks of cancer requires a rigorous and broad perspective spanning the physical and biological sciences," says Rakesh K. Jain, PhD, an investigator in the Edwin L. Steele Laboratories in the Department of Radiation Oncology at MGH and HMS.

In a review published in the journal Science, Jain and Steele Laboratories colleagues Hadi T. Nia, PhD, and Lance L. Munn, PhD, describe four distinct physical hallmarks of cancer that affect both cancer cells and the tumor microenvironment, contributing to both tumor growth and the development of resistance to powerful cancer drugs.

One widely accepted model of cancer holds that a normal cell goes rogue because of genetic mutations or an environmental insult. In this model, the altered cell starts replicating out of control and takes over normal tissues, displaying eight hallmarks that include the ability to promote and sustain the growth of tumors, evade immune system attempts to suppress growth, stimulate blood flow to tumors and both invade local tissues and metastasize (spread) elsewhere in the body.

But this model fails to take into account how physical processes affect tumor progression and treatment, say the authors. In addition to the aforementioned eight biological hallmarks of cancer proposed by Robert Weinberg, PhD, from MIT, and Douglas Hanahan, PhD, from the Swiss Federal Institute of Technology in Lausanne, Jain and colleagues propose adding four distinct physical hallmarks that capture the biomechanical abnormalities in tumors: elevated solid stress; elevated interstitial fluid pressure; increased stiffness and altered material properties; and altered tissue micro-architecture.

Three decades of research in the Steele Laboratories led to the discovery and clinical translation of the first two hallmarks. "Solid stresses are created as proliferating and migrating cells push and stretch solid components of the surrounding tissue. They are large enough to compress blood and lymphatic vessels in and around tumors, impairing blood flow and the delivery of oxygen, drugs and immune cells," Jain says.

Elevated interstitial fluid pressure is caused by abnormally permeable blood vessels in tumors leaking blood plasma into tissues surrounding the tumor, and by insufficient drainage of lymphatic fluid. The interstitial fluid carries various growth factors with it, causing edema (swelling), elution (release) of drugs and growth factors, and facilitating cancer invasion of local and distant tissues.

Increased stiffness is caused by the deposition of cellular matrix (scaffolding) and remodeling of tissues. This stiffness has traditionally been used as a diagnostic marker for tumor growth, and more recently it has come to be recognized as a marker for prognosis. Increased stiffness activates signaling pathways that promote proliferation, invasiveness and metastasis of cancer cells, Jain explains.

"Finally, when normal tissue architecture is disrupted by cancer growth and invasion, micro-architecture is altered," he says. "Stromal (supporting) cells, cancer cells and extracellular matrix adopt new organization. This changes the interactions between an individual cell and its surrounding matrix and cells, which affects signaling pathways associated with invasion and metastasis."

Jain says that with the review article in Science, he and his colleagues hope to bridge the gap between the physical and biological sciences "by exploring the biological origins and repercussions of the physical hallmarks of cancer from the perspectives of cancer biologists and oncologists - who work to understand and overcome the physical abnormalities at the bench and in the clinic - and from the perspectives of physicists and engineers who develop new models and strategies for research, diagnosis and treatment."

A chemist from RUDN University suggested an eco-friendly method for the synthesis of dapsone, a substance that inhibits the growth of malaria and leprosy agents. The main component of the new reaction is hydrogen peroxide that does not form environmentally destructive compounds, and the only by-product is simple water. Unlike other technologies, this method includes only one stage of dapsone production and does not require high temperatures. The catalyst of the reaction can be reused without any loss of efficiency. The results of the work were published in the Microporous and Mesoporous Materials journal.

Many think of leprosy as a disease of the past; however, about 200 thousand cases of it are registered in the world (mainly in India, Brazil, and Nepal) every year. It is treatable with antibiotics that prevent the growth of the Mycobacterium bacteria. On the contrary, malaria is one of the most widely spread diseases in the world with over 200 million cases annually. The spread of its agent (a protist from the genus Plasmodium) also can be inhibited with antibiotics. Dapsone is a safe and available drug that works in both cases and is included in the WHO Model List of Essential Medicines. However, its production is not eco-friendly, as the synthesis reaction requires high temperatures and the use of aggressive acids (such as sulphuric acid). A chemist from RUDN University suggested a green technology of dapsone synthesis that could potentially help expand its production and make the drug available to more patients.

Dapsone or diaminophenyl sulphone consists of two benzene rings with NH2 amino groups. The rings are connected with an oxidized atom of sulfur, or an SO2 group. To obtain dapsone, manufacturers oxidize its precursor in which the bond between the rings is formed by an SH group (sulfur and hydrogen). However, oxidation can also affect sensitive amino groups. Therefore, they have to be protected before the reaction starts--for example, by attaching special protective groups to them. The researcher from RUDN University developed a catalyst that provides for the oxidation of SH groups in the precursor with simple hydrogen peroxide. Hydrogen peroxide is considered the most environmentally friendly oxidizing agent because its only by-product is water. The reaction of oxidation takes place at room temperature, has only one stage, and requires no protection of amino groups.

"None of the earlier dapsone synthesis reactions can be called completely environmentally friendly as they happen in rigid conditions and have several stages: adding protective groups, synthesis, and their removal. This complexity increases the chances of by-products that should be removed from the reaction," said Raphael Luke, Ph.D., the head of the Molecular Design and Synthesis of Innovative Compounds for Medicine Science Center at RUDN University.

His team developed a wolfram-based catalyst from polyoxometalates by replacing certain wolfram atoms with vanadium. This increased the acidic properties of the catalyst and sped up the reaction, allowing it to take place even at low temperatures. To prevent the catalyst from being washed off from the reaction, the chemists encased the new compound in a porous material--a hydrogel made of propanoic acid and acrylamide. Thanks to it, the catalyst can be re-used at least three times without losing its efficiency. The team also identified the most optimal synthesis conditions and reagent concentration and managed to reach 100% oxidation of the dapsone precursor at 25? in only nine hours.

Scientists have revealed the molecular mechanism regulating the trafficking of lysosomes that increases the invasiveness of radioresistant cancer cells following radiotherapy.

Radiotherapy is an effective and commonly used treatment for cancer. However, there are varieties of cancer that become resistant to these therapies, and in some cases, these radioresistant cancers can become more invasive following treatment, worsening the prognosis for the patient.

Scientists from the Global Center for Biomedical Science and Engineering, a collaboration between Hokkaido University, Japan, and Stanford University, USA, have revealed the mechanism by which molecules called Arl8b and BORC cause increased invasiveness and metastasis in radioresistant cancer cells following radiotherapy. Their results were published in the journal Communications Biology.

Previous work has shown that trafficking of vesicles inside cells plays an important role in cancer cell invasiveness. A type of vesicle called the lysosome is particularly significant. Lysosomes are renowned as the vesicles responsible for degradation of molecules, but they are also involved in secretion of molecules that work for cell adhesion, tumor invasion and metastasis. In the current work the scientists investigated the molecular basis for these roles in radioresistant breast cancer.

They first confirmed that the trafficking of lysosomes was upregulated in the cancer cells following radiotherapy, enhancing the secretion of enzymes that degrade the connective material surrounding them, and therefore increasing invasiveness of the cancer cells. They further investigated the molecular mechanisms behind this activity and determined that a regulatory molecule, Arl8b, is primarily responsible for this process.

The active form of Arl8b is normally responsible for the trafficking of lysosomes within a cell. The scientists observed that in radioresistant cancer cells, the active form of Arl8b increases following radiotherapy, allowing it to interact with other molecules to enhance lysosome trafficking. Further, by knockdown of Arl8b, the scientists showed that this molecule was required for the increase of invasiveness and metastasis.

The researchers analysed data on breast cancer patients from The Cancer Genome Atlas (TCGA) to identify other molecules that may be involved. They found that, in addition to Arl8b levels, prognosis can be correlated with levels of a group of proteins called BORC complex, which is composed of eight subunits. High Arl8b levels correlated with poor prognosis; further, the prognosis could be stratified based on the levels of different BORC subunits. BORC is required for the association of Arl8b and lysosomes. The scientists showed that certain BORC subunits are required for the increased invasiveness of radioresistant cancer cells mediated by Arl8b; in addition, radiotherapy also upregulates genes responsible for the expression of certain BORC subunits.

In this study, the scientists uncovered the effect of radiotherapy on the lysosomal trafficking and some of the molecules controlling this process. Having elucidated the molecular basis for this mechanism, a larger dataset from human cancer patients must be analysed to validate the findings. Further, drugs that target this mechanism must be developed and evaluated as cancer therapies.

Dr. Jin-Min Nam and Dr. Yasuhito Onodera are part of the Radiation Biology group at the Global Center for Biomedical Science and Engineering (GCB), a collaboration between Hokkaido University, Japan, and Stanford University, USA. The group specializes in molecular and cellular oncology, and radiation biology.

WASHINGTON -- Teens who have good, supportive relationships with their teachers enjoy better health as adults, according to research published by the American Psychological Association. Perhaps surprisingly, although friendships are important to adolescents, the study did not find the same link between good peer relationships and students' health in adulthood.

"This research suggests that improving students' relationships with teachers could have important, positive and long-lasting effects beyond just academic success," said Jinho Kim, PhD, an assistant professor in the Department of Health Policy and Management at Korea University and author of the study. It was published in the journal School Psychology. "It could also have important health implications in the long run."

Previous research has suggested that teens' social relationships might be linked to health outcomes in adulthood - perhaps because poor relationships can lead to chronic stress, which can raise a person's risk of health problems over the lifespan, according to Kim. However, it is not clear whether the link between teen relationships and lifetime health is causal -- it could be that other factors, such as different family backgrounds, might contribute to both relationship problems in adolescence and to poor health in adulthood. Also, most research has focused on teens' relationships with their peers, rather than on their relationships with teachers.

To explore those questions further, Kim analyzed data on nearly 20,000 participants from the Add Health study, a nationally representative longitudinal study in the United States that followed participants for 13 years, from seventh grade into early adulthood. The participant pool included more than 3,400 pairs of siblings. As teens, participants answered questions such as, "How often have you had trouble getting along with other students?" "How much do you agree that friends care about you?" "How often have you had trouble getting along with your teachers?" and "How much do you agree that teachers care about you?" As adults, participants were asked about their physical and mental health. Researchers also took measures of physical health, such as blood pressure and body mass index.

Kim found that, as expected, participants who had reported better relationships with both their peers and teachers in middle school and high school also reported better physical and mental health in their mid-20s. However, when he controlled for family background by looking at pairs of siblings together, only the link between good teacher relationships and adult health remained significant.

This could be because previously reported links between peer relationships and physical health could actually reflect other, underlying factors about students' family background.

The results suggest that teacher relationships are even more important than previously realized and that schools should invest in training teachers on how to build warm and supportive relationships with their students, according to Kim.

"This is not something that most teachers receive much training in," he said, "but it should be."

The element chromium, despite having various applications, has a bad reputation. This is because exposure to chromium compounds leads to a higher risk of respiratory cancer and other damaging effects on human health. To add to this problem, chromium also happens to be a major contributor to water pollution due to its presence in industrial waste.

There is, however, a silver lining. As chemists have observed, the toxicity of chromium is dependent on its "valence state" (a state that is dictated by the number of electrons in the outer shell of an atom). Of the two stable states that chromium exhibits, "hexavalent chromium" or Cr(VI) and "trivalent chromium" Cr(III), the former is more toxic and soluble. Thus, chromium contamination can be mitigated by simply converting Cr(VI) to Cr(III) via a process called "reduction." Unfortunately, most approaches involved in reducing Cr(VI) to Cr(III) are either expensive and hazardous or have high energy requirements.

To this end, researchers have been focusing on the development of "photocatalysts," materials that can facilitate the reduction of harmful substances in the presence of light. The trick is to develop such a reaction using water as the solvent (as opposed to previously used organic solvents), such that they can be directly used to treat wastewater.

A team of researchers, led by Prof Takashiro Akitsu of Tokyo University of Science, has successfully done this, in a recent study published in New Journal of Chemistry. The team also included Yoshito Miyagawa, Tomoyuki Haraguchi (Tokyo University of Science, Japan), Arshak Tsatsuryan (University of Turin, Italy, and Southern Federal University, Russia), and Igor Shcherbakov (Southern Federal University, Russia). Prof Akitsu explains, "In our study, we developed a method to reduce Cr(VI) via light irradiation. We then applied it to an aqueous solvent to make its application easier."

In their study, the team synthesized copper (Cu(II)) complexes from a range of organic compounds. Through further analyses, they confirmed that these complexes, along with a photocatalyst called titanium oxide (TiO2), are involved in a photochemical reaction leading to the reduction of Cr(VI) in both methanol and water. Specifically, the group studied how the photocatalytic activity of the Cu(II) complex in methanol depended on the wavelength of incident light, while that of the Cu(II) complex with TiO2 in aqueous solution depended on the pH of the solution.

The findings revealed that, on one hand, the rate of Cr(VI) reduction in Cu(II)-methanol photochemical reaction is maximum for visible light in the wavelength range 460-495 nm. On the other hand, Cr(VI) reduction by the Cu(II)-TiO2 system under UV light was found to depend on the pH level of the aqueous solution, exhibiting high reduction efficiencies for acidic solutions with pH values

The study holds promise for the development of a novel wastewater treatment procedure that is both cost-effective and efficient. As Prof Akitsu puts it, "This is the first study to show the reduction of the toxic Cr(VI) into the relatively harmless Cr(III) in an aqueous solvent, which has direct implications in reducing water contamination."

With such a technology in place, we can certainly hope to reverse the adverse effects of industrial wastes on water bodies.

In the nearly two centuries since German physician Carl Wunderlich established 98.6°F as the standard "normal" body temperature, it has been used by parents and doctors alike as the measure by which fevers -- and often the severity of illness -- have been assessed.

Over time, however, and in more recent years, lower body temperatures have been widely reported in healthy adults. A 2017 study among 35,000 adults in the United Kingdom found average body temperature to be lower (97.9°F), and a 2019 study showed that the normal body temperature in Americans (those in Palo Alto, California, anyway) is about 97.5°F.

A multinational team of physicians, anthropologists and local researchers led by Michael Gurven, UC Santa Barbara professor of anthropology and chair of the campus's Integrative Anthropological Sciences Unit, and Thomas Kraft, a postdoctoral researcher in the same department, have found a similar decrease among the Tsimane, an indigenous population of forager-horticulturists in the Bolivian Amazon. In the 16 years since Gurven, co-director of the Tsimane Health and Life History Project, and fellow researchers have been studying the population, they have observed a rapid decline in average body temperature -- 0.09°F per year, such that today Tsimane body temperatures are roughly 97.7°F.

"In less than two decades we're seeing about the same level of decline as that observed in the U.S. over approximately two centuries," said Gurven. Their analysis is based on a large sample of 18,000 observations of almost 5,500 adults, and adjust for multiple other factors that might affect body temperature, such as ambient temperature and body mass.

The anthropologists' research appears in the journal Sciences Advances.

"The provocative study showing declines in normal body temperature in the U.S. since the time of the Civil War was conducted in a single population and couldn't explain why the decline happened," said Gurven. "But it was clear that something about human physiology could have changed. One leading hypothesis is that we've experienced fewer infections over time due to improved hygiene, clean water, vaccinations and medical treatment. In our study, we were able to test that idea directly. We have information on clinical diagnoses and biomarkers of infection and inflammation at the time each patient was seen.

While some infections were associated with higher body temperature, adjusting for these did not account for the steep decline in body temperature over time, Gurven noted. "And we used the same type of thermometer for most of the study, so it's not due to changes in instrumentation," he said.

Added Kraft, "No matter how we did the analysis, the decline was still there. Even when we restricted analysis to the

A key question, then, is why body temperatures have declined over time both for Americans and Tsimane. Extensive data available from the team's long-term research in Bolivia addresses some possibilities. "Declines might be due to the rise of modern health care and lower rates of lingering mild infections now as compared to the past," Gurven explained. "But while health has generally improved over the past two decades, infections are still widespread in rural Bolivia. Our results suggest that reduced infection alone can't explain the observed body temperature declines."

It could be that people are in better condition, so their bodies might be working less to fight infection, he continued. Or greater access to antibiotics and other treatments means the duration of infection is shorter now than in the past. Consistent with that argument, Gurven said, "We found that having a respiratory infection in the early period of the study led to having a higher body temperature than having the same respiratory infection more recently."

It's also possible that greater use of anti-inflammatory drugs like ibuprofen may reduce inflammation, though the researchers found that the temporal decline in body temperature remained even after their analyses accounted for biomarkers of inflammation.

"Another possibility is that our bodies don't have to work as hard to regulate internal temperature because of air conditioning in the summer and heating in the winter," Kraft said. "While Tsimane body temperatures do change with time of year and weather patterns, the Tsimane still do not use any advanced technology for helping to regulate their body temperature. They do, however, have more access to clothes and blankets."

The researchers were initially surprised to find no single "magic bullet" that could explain the decline in body temperature. "It's likely a combination of factors -- all pointing to improved conditions," Gurven said.

According to Gurven, the finding of lower-than-expected body temperatures in the U.S., and the decline over time, had a lot of people scratching their heads. Was it a fluke? In this study, Gurven and his team confirm that body temperatures below 98.6°F are found in places outside the U.S. and the U.K. "The area of Bolivia where the Tsimane live is rural and tropical with minimal public health infrastructure," he noted. "Our study also gives the first indication that body temperatures have declined even in this tropical environment, where infections still account for much morbidity and mortality."

As a vital sign, temperature is an indicator of what's occurring physiologically in the body, much like a metabolic thermostat. "One thing we've known for a while is that there is no universal 'normal' body temperature for everyone at all times, so I doubt our findings will affect how clinicians use body temperature readings in practice" said Gurven. Despite the fixation on 98.6°F, most clinicians recognize that 'normal' temperatures have a range. Throughout the day, body temperature can vary by as much as 1°F, from its lowest in the early morning, to its highest in the late afternoon. It also varies across the menstrual cycle and following physical activity and tends to decrease as we age.

But by linking improvements in the broader epidemiological and socioeconomic landscape to changes in body temperature, the study suggests that information on body temperature might provide clues to a population's overall health, as do other common indicators such as life expectancy. "Body temperature is simple to measure, and so could easily be added to routine large-scale surveys that monitor population health," Gurven said.

Because hydrogen fuel has high energy density and does not pollute the environment, it has now shown the potential to replace fossil energy. The hydrogen evolution reaction (HER) is one of the most promising hydrogen production methods as a half-reaction of the electrolysis of water. Currently, traditional Pt-based compounds are used as the most active electrocatalysts for hydrogen evolution reactions. However, Pt is relatively scarce and expensive. Therefore, designing and synthesizing highly efficient, stable, and inexpensive catalysts is a frontier topic in the field of water electrolysis.

Recently, Zhenxing Li and his team from China University of Petroleum (Beijing) have made exciting progress in the preparation of HER catalysts, using a simple one-pot method to synthesize ultra-small hollow ternary alloy nanoparticles, including PtNiCu nanoparticles, PtCoCu nanoparticles and CuNiCo nanoparticles. During synthesis, the displacement reaction and oxidative etching played important roles in the formation of hollow structures. The average size of PtNiCu nanoparticles is only 5 nm and contains only 10% Pt (Figure 1). The unique hollow structure and large specific surface area increase the degree of surface atom exposure, provide abundant active centers, and make PtNiCu nanoparticles exhibit excellent electrocatalytic activity and stability. In alkaline electrolyte, the overpotential of hollow PtNiCu nanoparticles at 10 mA cm-2 is as low as 28 mV versus RHE with a Tafel slope of 52.1 mV dec-1 (Figure 2), which was lower than those of commercial Pt/C. In addition, its mass activity is 5.62-fold higher than that of commercial Pt/C system. This effectively reduces the cost of platinum-based electrocatalysts and ensures that platinum atoms are used more efficiently.

By analyzing the bonding and antibonding orbital filling, the density functional theory (DFT) calculations show that the ΔGH* of PtNiCu nanoparticles is 0.05 eV, which is close to zero (Figure 3). In the hydrogen evolution reaction (HER) reaction process, the bonding strength of different metals to the hydrogen intermediate (H*) was in the order of Pt > Co > Ni > Cu. Thus, the excellent HER performance of hollow PtNiCu nanoparticles can be attributed to moderately synergistic interactions between the three metals and H*. Combining theoretical calculations with experimental data, this work provides a new strategy for the design and preparation of low-cost and high-performance HER catalysts.

WASHINGTON, October 27, 2020 -- To meet the Paris Agreement's daunting goal of preventing Earth's average temperature from rising more than 2 degrees Celsius (3.6 degrees Fahrenheit) above its level in preindustrial times, one of the best options for the energy economy will involve a shift to 100% renewable energy using solar energy and several other clean energy sources.

While no one knows exactly how an increase above 2 degrees Celsius would impact the planet, extraordinary climatic events would likely make many parts of the world uninhabitable with significant desertification, ocean acidification, and rise of seawater level, as well as floods, wildfires, hurricanes, and tornadoes.

In the Journal of Renewable and Sustainable Energy, from AIP Publishing, Pierre J. Verlinden, founder of AMROCK Pty. Ltd. in Australia, describes a model developed to predict what is necessary for the solar industry to meet Paris Agreement targets.

"Our planet is on the path of an average temperature increase of 4 degrees Celsius before the end of this century, with respect to the average Earth temperature before the industrial age, and the result will be catastrophic," Verlinden said.

Climate experts predict only 800 gigatons of carbon dioxide can be emitted before crossing the 2 degrees Celsius line. This means that at the current global emission of 36 gigatons per year, there is a 35-year window to reduce our emissions to zero.

One way to achieve this goal is to change the way energy is produced and consumed.

"Our vision is solar photovoltaics can play a central role in a transformed sustainable energy economy with 100% decarbonized electricity generation to power directly or indirectly -- through the production of green hydrogen or other synthetic fuels -- all energy sectors and industrial processes," said Verlinden.

The world will require, in addition to other renewable energy sources like wind and hydro, about 70 to 80 terawatts of cumulative capacity from solar photovoltaic systems. This represents more than 100 times the world's current solar photovoltaic installed capacity.

"Within the next 10 years, the industry needs to increase its production rate by a factor of about 30," he said.

A model developed by Verlinden and colleagues to predict the efficiency of solar cells and their cost to manufacture during the next few decades shows there "is no fundamental barrier to achieving this goal," he said.

The financial requirement to grow the production rate (capital expenditures to build new production lines) is decreasing at a rate of 18% per year, driven by productivity improvements and a combination of higher-throughput per tool, larger wafers, and improved cell efficiency.

"In terms of material sustainability, the only major issue is the use of silver for metallization of silicon solar cells," said Verlinden. "We need to reduce the use of silver in silicon solar cells from about 29 tons per gigawatt to less than 5 tons per gigawatt."

He cautions that while the objective of a cumulative installation of 70 or 80 terawatts by 2055 is achievable with a simple annual growth of the production rate of about 15% per year, pursuing this goal will result in a solar photovoltaic industry much larger than necessary. This could lead to a significant downturn when the objective of 80 terawatts is reached.

"This negative impact can be avoided if we right now accelerate the growth during the next 10 years and then stabilize the global production to 3 to 4 terawatts per year," Verlinden said.

Individuals with autism spectrum disorder (ASD) show reduced flexible behavior on a probabilistic reversal learning task, underpinned by less optimal learning within each developmental stage, according to a study published October 27 in the open-access journal PLOS Biology by Daisy Crawley of King's College London and Lei Zhang of University of Vienna, and colleagues. As noted by the authors, these findings provide novel insights into reduced flexible behavior in relation to clinical symptoms in ASD.

Flexible behavior requires learning from feedback to guide decisions, and adapting responses when such feedback changes. Studies of neurotypical individuals show that the cognitive processes underlying flexible behavior and reinforcement learning change as people pass through childhood and adolescence into adulthood. Despite the link often made between inflexible behavior and restricted, repetitive behavior - a core feature of ASD - evidence has been mixed and it has not been clear how this behavior changes developmentally in autistic individuals. To address this question, Crawley, Zhang and colleagues used a developmental approach and examined flexible behavior on a probabilistic reversal learning task in 572 children, adolescents and adults (ASD N=321; typical development, TD; N=251). In probabilistic reversal learning paradigms, participants typically must learn using feedback and adapt their responses when the rule changes to maximize favorable outcomes.

Autistic individuals showed on average more perseveration and less feedback sensitivity than TD individuals, resulting in poorer task performance. Computational modeling revealed that dominant learning mechanisms underpinning flexible behavior differed across developmental stages and reduced flexible behavior in ASD was driven by less optimal learning. In autistic children, perseverative errors were positively related to anxiety symptoms, and in autistic adults, perseveration was positively related to restricted, repetitive behaviors. According to the authors, this study is the first to elucidate a potential learning mechanism by which behavioral rigidity manifests in autistic adults.